I have created such additions based off of another mod, that I sent Rollie just a couple days ago.

For Warriors - when the overpower ability is available, it plays Homer Simpson saying "DOH!" and gives a message in the upper part of the screen to "OVERPOWER NOW!", for any other class besides warrior, it plays a "slap" sound. These are due to the fact that your target just dodged YOUR swing.

For Rogues - when the ability to riposte becomes available, it plays Nelsons famous "HA! ha!" from the Simpons and gives the message "RIPOSTE NOW!" on the screen. For any other class, it plays a generic parry wave used in the Combat Sounds mod.

For Hunters - when the ability to mongoose bite is available, it plays a bullet ricochet sound and gives the message "MONGOOSE BITE NOW!!" on the screen. For any other class, it plays the dodge/evade wave used in the Combat Sounds mod.

Some of these are louder than others, so some work still needs to be done to bring them all in line with each other.

Revenge I'm unsure of though. When does this ability become available? I have not played a warrior past lvl 20, so I've not seen that ability. I would need to know its true callout name as well to work up an addition for this, as well as the reason it becomes available (ie- the target dodge my swing, I dodge the targets swing, etc).